<template>
  <div class="channel-edit">
    <!-- 我的频道 -->
    <van-cell :border="false">
      <div slot="title" class="title-text">我的频道</div>
      <van-button class="edit-btn" size="mini" round type="danger" plain
        @click="isEdit = !isEdit"
   >{{ isEdit ? '完成' : '编辑' }} </van-button
      >
    </van-cell>
    <van-grid class="my-grid" :gutter="10">
      <van-grid-item
        class="grid-item"
        v-for="(channel, index) in myChannels"
        :key="index"
        @click="onMyChannelClick(channel, index)"
      >
      <!-- 将删除图标处理成插槽自定义按钮，并设置样式 -->
      <van-icon slot="icon" name="clear" v-show="isEdit && !fiexdChannels.includes(channel.id)"></van-icon> 
        <span
          class="text"
          :class="{ active: index === activeIndex }"
          slot="text"
          >{{ channel.name }}</span
        >
      </van-grid-item>
   </van-grid>
    <van-cell :border="false">
      <div slot="title" class="title-text">频道推荐</div>
    </van-cell>
    <van-grid class="recomment-grid" :gutter="10">
      <van-grid-item
        icon="plus"
        class="grid-item"
        v-for="channel in recommendChannele"
        :key="channel.id"
        :text="channel.name"
         @click="onAddChannel(channel)"
         
      >
      
      </van-grid-item>
    </van-grid>
  </div>
</template>

<script>
import { getAllChannels, addUserChannel  } from "@/api/channel.js";
import { mapState } from 'vuex'
import { setItem,getItem } from '@/utlis/storage'

export default {
  name: "ChannelEdit",
 props: {
    myChannels: {
      type: Array,
      required: true
    },
    activeIndex: {
      type: Number,
      required: true
    }
  },
  data() {
    return {
      allChannels: [], // 所有频道
      isEdit: false, //控制编辑状态
       fiexdChannels: [0] // 不需要编辑、删除的频道
    };
  },
 
  computed: {
     ...mapState(['user']),
    recommendChannele() {
         const channels = []
      //存储推荐频道数据
      this.allChannels.forEach( channel => {  //遍历所有频道
          const ret =this.myChannels.find(userChannels => {  //使用find查找我的频道数据
          return  userChannels.id===channel.id  //如果筛选的我的频道id等于 我的频道数据
      })
         if (!ret) {
        channels.push(channel)
      }
     });
      return channels 
    }
      },
  //   recommendChannele() {
  //     return this.allChannels.filter((channel) => {
  //       return !this.channel.find((Mychannel) => Mychannel.id === channel.id)
  //     })
      
  //   }
  // },
 
   created () {
    this.loadAllChannels()
  },
  methods: {
    async loadAllChannels() {
      try {
        const { data } = await getAllChannels()
        this.allChannels = data.data.channels
        // console.log(this.allChannels);
      } catch (error) {
        this.$toast('获取所有频道失效')
      }
    },
    // 添加频道
     async  onAddChannel(channel) {
      this.myChannels.push(channel) //添加到我的频道也就是文章列表
      // 数据持久化处理
     if (this.user) {
       // 已登录，把数据请求接口放到服务器
       try {
         await addUserChannel({
           id: channel.id, // 频道 ID
           seq: this.myChannels.length // 序号
         })
       } catch (error) {
         this.$toast('保存失败，请稍后再试')
       }
     } else {
       // 未登录，把数据存储到本地
       setItem('TOUTIAO_CHANNELS', this.myChannels)
     }
   },
    // 切换频道
    onMyChannelClick(channel, index) {
      if (this.isEdit) {
        // 如果是固定频道，则不删除
        if (this.fiexdChannels.includes(channel.id)) {
          return
        }

        // 删除频道项
        this.myChannels.splice(index, 1)

        // 如果要删除的激活频道之前的频道，则更新激活的频道项
        // 参数1：要删除的元素的开始索引
        // 参数2：要删除的个数，如果不指定，则从参数 1 开始一直删除
        if (index <= this.activeIndex) {
          // 让激活频道索引 - 1
          this.$emit('update-active', this.activeIndex - 1,true)
        }
      } else {
        // 非编辑状态，指向切换频道
        this.$emit('update-active', index,false)
      }
    }
  }
};
</script>

<style scoped lang="less">
.channel-edit {
  padding: 85px 0;

  .title-text {
    font-size: 32px;
    color: #333;
  }

  .edit-btn {
    width: 104px;
    height: 48px;
    font-size: 26px;
    color: #f85959;
    border: 1px solid #f85959;
  }

  /deep/ .grid-item {
    width: 160px;
    height: 86px;
    .van-grid-item__content {
      white-space: nowrap;
      background-color: #f4f5f6;
      .van-grid-item__text,
      .text {
        font-size: 22px;
        color: #222;
        margin-top: 4px !important;
      }
      .active {
        color: red;
      }
        .van-grid-item__icon-wrapper {
     position: unset;
   }
    }
  }

  /deep/ .my-grid {
    .grid-item {
      .van-icon-clear {
        position: absolute;
        right: -10px;
        top: -10px;
        font-size: 30px;
        color: #cacaca;
        z-index: 2;
      }
    }
  }

  /deep/ .recomment-grid {
    .grid-item {
      width: 160px;
      height: 86px;
      .van-grid-item__text,
      .text {
        font-size: 22px;
        color: #222;
        margin-top: 4px !important;
      }
      .van-grid-item__content {
        flex-direction: row;
        .van-icon-plus {
          font-size: 22px;
          line-height: 22px;
          margin-right: 6px;
        }
      }
    }
  }
}
/deep/.van-grid-item__icon-wrapper {
  position: unset !important;
  .active {
    font-size: 18px;
    color: #b3b5ce !important;
  }
}
// .van-grid-item__icon-wrapper {
//           /deep/
//         }
</style>